Circulating Tumor Cell Microseparator Based on Lateral Magnetophoresis and Immunomagnetic Nanobeads

Abstract

This paper presents a circulating tumor cell (CTC) microseparator for isolation of CTCs from human peripheral blood using immunomagnetic nanobeads with bound antiepithelial cell adhesive molecule (EpCAM) antibodies that specifically bind to epithelial cancer cells. The isolation is performed through lateral magnetophoresis, which is induced by high-gradient magnetic separation technology, involving a ferromagnetic wire array inlaid in the bottom substrate of a microchannel. Experimental results showed that the CTC microseparator isolates about 90% of spiked CTCs in human peripheral blood at a flow rate of up to 5 mL/h and purifies to approximately 97%. The overall isolation procedure was completed within 15 min for 200 μL of peripheral blood. CTCs from peripheral blood of patients with breast and lung cancers were isolated with the CTC microseparator, and the results were compared with those of healthy donors. Using a fluorescence-based viability assay, the viability of CTCs isolated from peripheral blood of patients with cancer was observed. In addition, the usefulness of the CTC microseparator for subsequent genetic assay was confirmed by reverse-transcriptase polymerase chain reaction (RT-PCR) amplification of cancer-specific genes using CTCs isolated from patients with cancer.

Rational Design of Materials Interface for Efficient Capture of Circulating Tumor Cells

“…By combing the immunomagnetic separation strategy and microfluidic technique, Immunomagnetic‐based microfluidic systems have also been developed for efficient CTCs capture and isolation 69, 70, 71, 72, 73, 74, 75, 76. Hoshino et al developed an immunomagnetic‐based microfluidic device for CTCs capture 69.…”

Advances in steady-state continuous-flow purification by small-scale free-flow electrophoresis

“…Free-flow magnetophoresis separates particle analytes from a stream of sample, which is driven continuously through a magnetic field and typically orientated orthogonally to the flow. Magnetophoresis, in free-flow form, has been applied to the separation of cancer cells from normal cells [17,18], DNA purification [19], water purification [20,21], and nanoparticle (NP) purification [22].…”

Microfluidic immunomagnetic cell separation using integrated permanent micromagnets

“…Compared to micro-electromagnets, such micro-patterned flux concentrators allow the production of substantially stronger magnetic fields while avoiding heat generation. Inglis 14 and coworkers followed by Adams et al 15 and more recently by Kim et al 16 have performed continuous flow immunomagnetic cell separation in microfluidic devices using integrated soft magnetic stripe structures inclined at an angle to the flow direction, and magnetized by an external bulk permanent magnet.…”